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How can I check if a program exists from a Bash script?
How would I validate that a program exists, in a way that will either return an error and exit, or continue with the script?
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@selector() in Swift?
I'm trying to create an NSTimer in Swift but I'm having some trouble.
23 Answers
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How to check for an undefined or null variable in JavaScript?
We are frequently using the following code pattern in our JavaScript code
24 Answers
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Difference between return and exit in Bash functions
What is the difference between the return and exit statement in Bash functions with respect to exit codes?
10 Answers
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Why should I use the keyword “final” on a method parameter in Java?
I can't understand where the final keyword is really handy when it is used on method parameters.
12 Answers
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Xcode 6 Bug: Unknown class in Interface Builder file
I upgraded to Xcode 6 beta 4 and now my App continuously crashes with the message
52 Answers
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What are file descriptors, explained in simple terms?
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In simple words, when you open a file, the operating system creates an entry to represent that file and store the information about that opened file. So if there are 100 files opened in your OS then there will be 100 entries ...
Constructor overload in TypeScript
Has anybody done constructor overloading in TypeScript. On page 64 of the language specification (v 0.8), there are statements describing constructor overloads, but there wasn't any sample code given.
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What does new self(); mean in PHP?
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self points to the class in which it is written.
So, if your getInstance method is in a class name MyClass, the following line :
self::$_instance = new self();
Will do the same as :
self::$_instance = new MyClass();
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Use 'import module' or 'from module import'?
I've tried to find a comprehensive guide on whether it is best to use import module or from module import . I've just started with Python and I'm trying to start off with best practices in mind.
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